<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    .box {
        width: 300px;
        height: 300px;
        background-color: hotpink;
        padding: 5px;
        border: 5px solid black;
        margin: 5px;
    }

    .box1 {
        width: 300px;
        height: 300px;
        background-color: indigo;
        box-sizing: border-box;
        border: 5px solid black;
        margin: 5px;
    }
</style>

<body>
    <div class="box"></div>
    <div class="box1"></div>
</body>

</html>